Removal of SO2 from smelting flue gas by using copper tailings with MnSO4: factors optimization by response surface methodology.

ABSTRACT

The abatement of SO2 and the utilization of copper tailings are identified as two attention-attracting environmental issues in the copper smelter. In this study, to improve the flue gas desulfurization performance and the utilization of copper tailings, SO2 removal from smelting flue gas by using copper tailings combined with MnSO4·H2O was investigated. The effects of operation variables, including inlet SO2 concentration, absorption temperature, slurry concentration, and MnSO4·H2O amount, on the flue gas desulfurization performance were studied based on the response surface method. It was found that the effect of operation variables on SO2 removal follows the descending order the inlet SO2 concentration, MnSO4·H2O concentration, absorbent temperature, and solid-liquid ratio. The interaction between the inlet SO2 concentration and MnSO4·H2O concentration is an important factor for breakthrough sulfur capacity. Elevated temperature and high initial SO2 concentration inhibited the efficient removal of SO2. Moreover, a proposed equation exhibits good consistency in the prediction for the breakthrough sulfur dioxide capacity. Therefore, the results can provide a reliable reference and basis for industrial application for flue gas desulfurization with copper tailings.